Check out our Wiki article on full-text processing to find out more:
http://docs.basex.org/wiki/Full-Text
___________________________
On Wed, Jan 2, 2013 at 11:17 PM, Christian Grün
<christian.gr...@gmail.com> wrote:
> Hi David,
>
> due to the complexity of XQuery, it’s often a big challenge for the
> query optimizer to find out if an index can be used or not. This is
> the reason why some XML database don’t even try to rewrite queries for
> index access.
>
> What you can always do is: directly address the available index
> structures via the Full-Text and Index modules [1,2]. This will give
> you the guarantee that the index is indeed utilized.
>
> I'm sure there are also ways to rewrite your existing query in order
> to ensure index access, but I’d first need some more time to get into
> this. As a general note, you can help the optimizer by directly
> specifying the addressed database in your query. The following two
> examples may illustrate this. Query A und B will be optimized for
> index access, while Query C won’t (well, at least not in BaseX ≤ 7.5):
>
> Query A
> db:open("db")//*[text() contains text { "A","B" }]
>
> Query B
> let $terms := ("A", "B")
> for $x in db:open("db")//*
> where $x/text() contains text { $terms }
> return $x
>
> Query C
> declare function local:x($db, $terms) {
> db:open($db)//*[text() contains text { $terms }]
> };
> let $terms := ("A", "B")
> let $db := "db"
> return local:x($db, $terms)
>
> Best,
> Christian
>
> [1] http://docs.basex.org/wiki/Full-Text_Module
> [2] http://docs.basex.org/wiki/Index_Module
> ___________________________
>
> On Wed, Jan 2, 2013 at 10:59 PM, David Stuebe <dstu...@asascience.com> wrote:
>>
>> Hi Chris
>>
>> I did look at the Query Info in the Gui and it seems you are correct. The
>> complex query I created is not utilizing the full text index.
>>
>> Details here:
>> https://gist.github.com/4438473
>>
>> The gist contains query info for the complex search that I created and for a
>> simple one that just executes the 'contains text' clause.
>>
>> The compile statement for the simple query includes the following line:
>> "applying full-text index"
>> The complex query does not…
>>
>>
>> So what to do now? How do I figure out why basex is not using the full text
>> index as the initial step in limiting the results of my search?
>>
>> Thanks
>>
>> David
>>
>>
>> From: "basex-talk-requ...@mailman.uni-konstanz.de"
>> <basex-talk-requ...@mailman.uni-konstanz.de>
>> Reply-To: "basex-talk@mailman.uni-konstanz.de"
>> <basex-talk@mailman.uni-konstanz.de>
>> Date: Tue, 1 Jan 2013 06:00:02 -0500
>> To: "basex-talk@mailman.uni-konstanz.de"
>> <basex-talk@mailman.uni-konstanz.de>
>> Subject: BaseX-Talk Digest, Vol 37, Issue 1
>>
>> Message: 1
>> Date: Mon, 31 Dec 2012 20:56:01 +0100
>> From: Christian Gr?n <christian.gr...@gmail.com>
>> To: David Stuebe <dstu...@asascience.com>
>> Cc: Kyle Wilcox <kwil...@asascience.com>,
>> "basex-talk@mailman.uni-konstanz.de"
>> <basex-talk@mailman.uni-konstanz.de>
>> Subject: Re: [basex-talk] Initial xquery for full text and geospatial
>> search of ISO 19115 docs
>> Message-ID:
>> <cap94bnpneuwgumgl-k2zmw6gcd4wqnc82kbr5es8h+brz1f...@mail.gmail.com>
>> Content-Type: text/plain; charset=windows-1252
>>
>> Hi David,
>>
>> thanks for the insight into your project. It may be that the full-text
>> index is not utilized by your XQuery expression. Did you have a look
>> at the query info (e.g. via GUI, InfoView, or -V on command line)? Did
>> you manage to write simpler queries that are processed faster?
>>
>> Best,
>> Christian
>> ___________________________
>>
>> On Mon, Dec 31, 2012 at 7:31 PM, David Stuebe <dstu...@asascience.com>
>> wrote:
>>
>>
>>
>>
>> Hi Basex Folks
>>
>> I have written a simple minded xquery script which can be used in a post to
>> search ISO 19115 metadata documents.
>> As I am a newbie to xquery and basex I expect that is much that I could do
>> to improve performance, but currently searches take up to 15 seconds. The
>> server hardware is not blazing fast and we are running inside tomcat? but
>> that is certainly not acceptable for a database which is still quiet small.
>> Initially it was fine, responding in less than a second, but when we
>> expanded from less than 100 docs to about 35000 the time grew at least
>> linearly. I am hoping this is due to my poor xquery programming or a setting
>> on the server.
>>
>> Here is the query we are running using a post request with the declared
>> variables at the bottom filled in by the UI:
>> https://github.com/asascience-open/glos_catalog/blob/master/queries/full_search.xml
>>
>> Here are some of the ISO xml documents that we have in our basex DB:
>> https://github.com/asascience-open/glos_catalog/tree/master/ISOs
>>
>> It is used by this site: http://explorer.glos.us/
>> To provide geospatial metadata search. Fill in a text value like "water" or
>> "temperature" in the search box in the top right?
>>
>> The server is here: http://64.9.200.113:8080/BaseX73/
>> User Name: user
>> Password: glos
>> ACL: read only
>>
>>
>> I am hoping it is as simple as a setting on the basex server. Here is the
>> current server info:
>>
>> info database
>> Database Properties
>> Name: glos
>> Size: 422 MB
>> Nodes: 17045388
>> Documents: 34922
>> Binaries: 0
>> Timestamp: 27.12.2012 00:58:03
>>
>> Resource Properties
>> Timestamp: 22.12.2012 01:43:05
>> Encoding: UTF-8
>> Whitespace Chopping: ON
>>
>> Indexes
>> Up-to-date: true
>> Text Index: ON
>> Attribute Index: ON
>> Full-Text Index: ON
>>
>> The index info is available here:
>> https://github.com/asascience-open/glos_catalog/blob/master/queries/glos_index_info.txt
>>
>>
>>
>> David Stuebe
>>
>> Scientist & Software Engineer ? RPS ASA
>>
>> 55 Village Square Drive
>> South Kingstown, RI 02879-8248
>>
>> Tel: +1 (401) 789-6224
>>
>> Email: david.stu...@rpsgroup.com
>> www: asascience.com | rpsgroup.com
>>
>> A member of the RPS Group plc
>>
>>
>> _______________________________________________
>> BaseX-Talk mailing list
>> BaseX-Talk@mailman.uni-konstanz.de
>> https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk
>>
>>
>>
>>
>> _______________________________________________
>> BaseX-Talk mailing list
>> BaseX-Talk@mailman.uni-konstanz.de
>> https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk
>>
_______________________________________________
BaseX-Talk mailing list
BaseX-Talk@mailman.uni-konstanz.de
https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk
